1. Field of the Invention
The present invention relates to an improvement of the lock mechanism suitable for fixing a matter such as the collapsible seat to the fixing object.
2. Prior Art
In the case of the collapsible seat 1 which is used as the seat for vehicles, for example, two legs 2 are pivoted on a floor 3 and the remaining two legs 4 each having a lock mechanism consisting of a hook 5 and a bumper are detachably attached and fixed to the floor 3 in such a way that the lock mechanism are engaged with strikers 7 on the floor 3, as shown in FIG. 1.
This lock mechanism is also used as the means for fixing seat backs, as disclosed by a pre-opened Japanese Utility Model Sho-54/63703 or the like.
In the case of the above-mentioned conventional lock mechanism, however, the front end of the striker attached to the fixing member is struck against the bumper when the claw portion of the hook is temporarily retreated, and it is then held and fixed between the bumper and the claw of the hook. When the front end of the striker is engaged with and released from the lock mechanism like this, therefore, it is slidably contacted with the bumper, thereby causing large operation resistance because of friction. This needs substantially large operation force to achieve locking and unlocking. In addition, the bumper is worn and the lock mechanism becomes thus unsteady as time goes by, thereby causing a problem in durability.